You can see the proof here: http://giphy.com/gifs/pantheon-files-rename-menu-bug-l4FGtN9vJ8HTtd9Dy/fullscreen
The problem is already described here: How can I copy/paste the file NAME?
And the answer fom 'Aditya ultra' doesn't work. Nothing happens when you press on the 'paste' option.
But pressing 1) rename and 2)Ctrl + V works. It's very strange.
The issue is also present on another laptop where pantheon-files uses the default elementary theme, so the theme doesn't cause the issue.
It is really time to fix this, this is one of the most important things that users do with a file manager.